While we may think of our digestive system as simply breaking down the foods we eat and then getting rid of the waste, it is truly a more complicated system that plays an important role in our overall health. The gastrointestinal tract (its official name or GI tract for short) is home to a wide array of bacteria. These bacteria help the GI tract to do its job as a barrier that allows nutrients to be absorbed while keeping toxins and disease causing microorganisms from entering into the body. In fact, about 70 percent of the body's immune function is in the GI tract.
We have long recognized the positive effects of probiotics on the GI tract and are learning more about the role of prebiotics. These are considered functional elements in foods that provide health benefits above and beyond basic nutrition. Prebiotics are non-digestible fiber that may stimulate the growth and activity of the "good" bacteria found in the intestines. Probiotics on the other hand are "live" microorganisms which when consumed in adequate amounts may result in a health benefit.
When it comes to probiotics, the most familiar are Lactobacilli and Bifidobacteria found mainly in cultured dairy products such as yogurt and kefir. Streptococcus thermophiles and Saccharomyces are other strains of bacteria commonly found in fermented foods like tempeh, miso, kimchi and sauerkraut. To be beneficial there has to be an adequate number of bacteria and they have to be active or live. These probiotics help to maintain the balance of "good" bacteria in the GI tract, allowing it to do its job.
Probiotics are also available in supplement form such as powders, creams, capsules and suppositories. Anyone can consume food sources of probiotics, but if you are considering a supplement be sure to check with your health care provider first and do your research before selecting a supplement.
One of the benefits of probiotics appears to be in the treatment of acute diarrhea and antibiotic associated bouts of diarrhea. In these cases, the duration of symptoms is shortened. There is also support that probiotics aid in the treatment of atopic eczema. Other potential benefits being researched include, reduction in the symptoms of lactose intolerance, decreased risk of colorectal cancer, management of irritable bowel syndrome and prevention of certain allergies.
Since probiotics are "living" organisms they must have a source of nourishment and that is where prebiotics enter the picture. Prebiotics are natural, non-digestible carbohydrates in food such as oligosaccharides, inulin and polydextrose, that promote growth of the normal, healthy bacteria already in our gut. Good food sources of prebiotics include bananas, berries, legumes, garlic, onions, asparagus, artichokes, leeks, nuts, seeds and whole wheat. Less is known about the role of prebiotics in maintaining gut health, but current research points to the fact they may improve calcium and magnesium absorption, increase resistance to infection and reduce risk for other intestinal problems.
So how can you reap the benefits of this "dynamic duo?" First, when it comes to grocery shopping be sure to look for yogurt that contains "live an active cultures" not "made with active cultures." Be willing to try new foods such as kimchi (fermented vegetables), kefir or miso (fermented soybean paste). Since pre and probiotics work together, plan your meals to include combinations of foods, such as topping yogurt with bananas or stir-frying asparagus with tempeh.
If you want to experiment with something new, here are some tips to introduce kimchi (kim-chee), a spicy condiment made with fermented vegetables and Asian seasonings. It can be found in the produce section of the grocery store. You can mix it into rice, stir into soups or stews, mix with pasta or use as a topping on hamburgers. All of this designed to keep your "tummy" health and happy!
- Duyff, R. American Dietetic Association Complete Food and Nutrition Guide. 4th ed., Hoboken, N.J.: John Wiley & Sons, 2012
- "Functional Foods Fact Sheet: Probiotics and Prebiotics." Food Insight, May 23, 2014.
- Newgent, J. "Prebiotics and Probiotics: Creating a Healthier You." Retrieved April 15, 2016.